Voyager

The year is 2100, and Earth is dying. Centuries of neglect followed by a global war against the AIs have left Earth barely inhabitable. Fortunately for humanity one person had the vision to terraform Mars without the endorsement of any government or space agency.

Elon Musk had secretly been using his companies to terraform Mars and make it habitable. For saving the human race the first settlers renamed Mars to Musk.

Once settled on Mars humans began finding artifacts from other civilizations. One such artifact, a downed alien ship, led to the development of spaceships as we know now.

The humans figured out contragravity lifters, gravity plating, reactionless drives, and hyperdrive technology from the craft. The opening up of space led to the colonization of other inhabited world. This led to first contact with the Maru.

Human colonies had started disappearing, along with large swaths of plant and animal life on the colonized planets. After the third colony disappeared the humans finally made contact with the entities responsible.

They witnesses the Maru and their organic ship, feeding on the planet, or bio-scooping as they later learned. The humans declared war on the Maru. The Maru claimed ignorance of the human colonies on their farm planets.

The war went on for nearly a decade at a near stalemate. Until a common enemy appeared. The Varo arrived on the scene and claimed that the humans and Maru were violating their space. This led to conflict and both races realized they were extremely outclassed.

The tentative peace from a common enemy led to the development of the Terran-Maru Science Enclave. The best scientist from both races working together to develop new technologies for combating the Varo. This has led to amazing developments in medicine and terraforming, but little usable tech for fighting the Varo.

The Varo have limited their conflict to the systems they stake claim on. The Varo have no claim on the home systems for the humans or Maru.